It is well known that windshield wipers can become stuck, or frozen, to a vehicle windshield in certain inclement weather. Vehicle operators who park their vehicles outdoors at night or during the day often find their vehicle covered in snow and/or ice. In these situations, clearing the windshield of the snow and/or ice is not always sufficient to unstick the windshield wipers from the windshield. Typically, the vehicle operator will have to physically move the windshield wiper to overcome the retentive force created by the snow and/or ice. In addition to being a nuisance for the vehicle operator, physically moving the windshield wiper can also result in damage to the windshield wipers or wiper blades.
In other scenarios, the vehicle owner may start the vehicle allowing it time to warm up and at least partially clear the windshield. This may be done utilizing a remote vehicle start function or manually. In such scenarios, the vehicle operator turns on a rear window heater and a defroster to warm the front windshield. Typically, however, the vent through which the warm air blows onto the front windshield in the defrost mode contacts the window above a zone of the windshield where the windshield wipers typically reside when not in use, in other words, the defroster only warms a portion of the windshield excluding a windshield wiper park zone. Again, the windshield may be substantially cleared of snow and/or ice by the defroster but the windshield wiper may remain frozen to the windshield within the windshield wiper park zone.
Although mechanisms have been developed to warm the windshield wiper park zone, these mechanisms are limited primarily to a pre-warming sequence or a sequence which remains on throughout the entire time the vehicle is running. In other words, warming of the windshield wiper park zone whether for a pre-warming period or the entire time the vehicle is running is only initiated by the vehicle owner starting the vehicle, whether manually or remotely, to allow the vehicle time to warm up and at least partially clear the windshield.
While these mechanisms have proven useful in these scenarios to warm the windshield wiper park zone sufficient to release the windshield wipers from the windshield, they each suffer from certain drawbacks. The pre-warming sequence, for example, does not account for scenarios where the windshield wiper park zone refreezes after the pre-warming period elapses and the windshield wipers become stuck during operation of the vehicle. In such a scenario, the vehicle operator has to cease operating the vehicle to address the issue manually, continue operating the vehicle without windshield wiper function, restart the car in order to re-engage the pre-warming sequence, or engage a human machine interface (HMI) to initiate a new warming sequence if the particular vehicle has an HMI. The warming sequence which occurs throughout the entire period of time the vehicle is operating likewise has drawbacks. Primarily, the continuous warming sequence consumes a significant amount of current throughout the sequence. Some, or even most, of this current consumption could be occurring during periods where warming is no longer required due to ambient temperature increases and/or a lack of need for windshield wiper function.
Accordingly, a need exists for a way to prevent a windshield wiper from freezing to a windshield in the first instance which eliminates the need for a pre-warming sequence, a continuous sequence, or manually engaged sequences utilizing HMI. Ideally, a preventative sequence would be initiated when ambient conditions of the vehicle are adverse indicating or even suggesting the possibility of precipitation or other adverse condition. Adverse conditions may include any indicator of precipitation including, for example, an ambient temperature near or below freezing, actual precipitation falling as sensed by a rain sensor, a humidity sensor, or information obtained from a camera mounted to the vehicle or otherwise. Even more, information concerning weather obtained from another source such as a radio, a computer, a receiver, or a mobile device, or applications supported thereby, may be used to initiate a preventative sequence when ambient conditions indicate or suggest the possibility of precipitation or other adverse condition.
Such a preventative sequence would be required to occur prior to freezing which could result in false positives. Accordingly, the sequence should be able to determine whether the windshield wiper is frozen to the windshield and to adjust the sequence accordingly. The sequence could also extend until the ambient conditions are no longer adverse, i.e., they are sufficient to avoid freezing.